May 28, 2013

Decoded Camel Genome To Unveil Secrets Of Evolutionary History

Researchers have sequenced the genome of a Bactrian camel named Mozart, laying down the foundation for future scientific work on these large desert mammals.

Camels consist of two species, which include the one-humped dromedary and the two-humped Bactrian camel. The animals have the ability to carry heavy loads in harsh desert environments over long distances. They can survive weeks in hostile environments without food or water. Researchers at the Vetmeduni Vienna wanted to learn a bit more about the genetic code of the camel.

Researcher Pamela Burger, who heads one of the few research groups to study camel genetics, was interested in learning about the domestication of camels which took place around 3,000 to 6,000 years ago. Burger and her colleagues believe that the animal´s DNA code could provide clues on the breeding strategies and selection processes that were applied by humans at that time.

The scientists found 116,000 single nucleotide polymorphisms (SNPs) in the genetic sequence of the Bactrian camel. SNPs are single base-pair changes found in a DNA strand that provide the basis for studying relationships among species and between single animals. The genetic relationship between the Bactrian camel and the dromedary camel is a close one. They found that 85 percent of the genomic sequence expressed in the dromedary can be found in the Bactrian camel as well.

"Mozart℠s genome provides us with the basis for further comparative research on other camelids such as dromedary, lama and alpaca," said Burger, who also authored the study which appeared in the Journal of Heredity.

The lack of basic genetic data on camel species has hampered researchers like Burger from studying the animal's genome. These genomes will also help scientists understand more about the evolution of the camel and its predecessors, such as how one recently discovered 3.5-million-year-old fossil may have played into its evolutionary family tree.

In March, researchers discovered the fossilized remains of a giant prehistoric species of camel in the far northern regions of Canada. The discovery implies that modern camels are descendants from ancestors which lived within the Canadian Arctic Circle. The paleontologists found 30 fossil fragments of a leg bone that dates back to the mid-Pliocene Epoch period. They believe the creature would have been similar in appearance to current camels, but with a thicker coat to keep it warm.

“We now have a new fossil record to better understand camel evolution, since our research shows that the Paracamelus lineage inhabited northern North America for millions of years, and the simplest explanation for this pattern would be that Paracamelus originated there,” explained paleontologist Dr. Natalia Rybczynski of the Canadian Museum of Nature.

“So perhaps some specializations seen in modern camels, such as their wide flat feet, large eyes and humps for fat may be adaptations derived from living in a polar environment.”